Effect of Manganese Alloying on Infrared Detectors Made of Pb_1-xMn_xTe/CdTe Multilayer Composite

The properties of Pb_1-xMn_xTe/CdTe multilayer composite grown by molecular beam epitaxy on a GaAs substrate were studied. The study included morphological characterization by X-ray diffraction, scanning electron microscopy, secondary ion mass spectroscopy, as well as electron transport and optical spectroscopy measurements. The main focus of the study was on the sensing properties of photoresistors made of Pb_1-xMn_xTe/CdTe in the infrared spectral region. It was shown that the presence of Mn in the Pb_1-xMn_xTe conductive layers shifted the cut-off wavelength toward blue and weakened the spectral sensitivity of the photoresistors. The first effect was due to an increase in the energy gap of Pb_1-xMn_xTe with an increase in Mn concentration, and the second was due to a pronounced deterioration in the crystal quality of the multilayers owing to the presence of Mn atoms, as shown by the morphological analysis.